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SdKfz 101 Panzerkampfwagen I (PzKpfW I) / Panzer 1

Nazi Germany (1935)

Detailing the development and operational history of the SdKfz 101 Panzerkampfwagen I (PzKpfW I) / Panzer 1 Light Tank.

 Entry last updated on 4/1/2017; Authored by Dan Alex; Content ©

  SdKfz 101 Panzerkampfwagen I (PzKpfW I) / Panzer 1  
Picture of SdKfz 101 Panzerkampfwagen I (PzKpfW I) / Panzer 1 Light Tank

The Panzer I Light Tank began the long line of successful, fast-moving tanks common to the German blitzkrieg.

Few could have known what the inception of the Panzer I into the German Army inventory during the middle portion of the 1930s had in store for the future of Europe. Though something of a failure as a combat vehicle, the Panzer I went on to begin the long and successful family line of tanks encountered in the German Army through all of World War 2. Each system grew progressively larger and more powerful (and equally as lethal) than her predecessor but they all had the Panzer I to thank for their origins. The little tank served through the first major invasions of Europe, was modified to fit other battlefield-required forms and fought on into 1944. It is reported that some 2,800 Panzer I tanks of all types were ultimately produced.

Note: To help the reader along, it is important to note the German designation convention for its military vehicles. The abbreviation Pz.Kpf.W. covers "Panzerkampfwagen" and translates to "armored fighting vehicle". Likewise, the abbreviation Sd.Kfz. covers "Sonderkraftfahrzeug" and translates to "special motor vehicle". Ausf is the general term used to cover "model" or "mark" in showcasing a variant of note. Taking all this into account, the Panzer III can also be known by the designation of Pz.KpfW. I as well as Sd.Kfz. 101 while any model variants are covered in the convention of Ausf. A, Ausf. B, Ausf. C and so on. "Ausf." is the abbreviated form of the word "Ausfuhrung meaning simply "model" or "design".


While the British became the first army in the world to field a tank in combat during World War 1, it was surprising to note that the German Army was not quite so accepting of the concept at first. The 28-ton British Mark I, a typical rhomboidal-shaped two-tracked tank, armed with 2 x 57mm cannons on side sponsons and five machine guns scattered about the design, was featured in the key Battle of the Somme - the Allied attempt to break through the stubborn German defenses on September 15th, 1916. Despite mixed results in the ensuing action, the modern battlefield was forever changed.

The Germans finally caught on to this change in the wind. Development began on the A7V, a boxy comical 30-ton creation that fitted up to 18 men inside as well as a 57mm cannon along with six machine guns and 2 x Daimler-Benz engines in a smelly and noisy interior (the British tanks were no better in terms of internal operating environments for their crews) and unleashed the steel beasts on March 21st, 1918. Despite its addition to the German Army arsenal at this time, the A7V was to only partake in the final German offensive of World War 1.
Picture of the SdKfz 101 Panzerkampfwagen I (PzKpfW I) / Panzer 1 Light Tank
Picture of the SdKfz 101 Panzerkampfwagen I (PzKpfW I) / Panzer 1 Light Tank

Hog-Tying the German War Machine

As Imperial Germany eventually fell to the Allies, the victors pushed for severe restrictions on the country's war-making capabilities. While the Ottoman Empire was being dismantled out east, Germany took the brunt of the blame to the west and was forced into signing the Treaty of Versailles in June of 1919. Limitations for the land army included a 100,000-strong infantry army, absolutely no tanks of any kind and just a few armored vehicles for spot duty. The German Army of the interwar years, as it stood, was a shell of its former self and far cry from the leviathan that would arise in the 1930s.

Dismantled but not wholly out of the game, some within the German Army ranks were already at work on skirting the rules of the Versailles Treaty. One such individual became Commander-in-Chief Hans von Seeckt. Seeckt took to heart the lessons learned in the Great War and set about in rewriting the foundation of the German Army. He was one to accept the value of armored warfare early on, that it would inevitably replace cavalry of wars gone by, and envisioned a future where a mobile mechanized army would be the order of the day in ensuring a proper and overwhelming victory.

By 1926, German Army doctrine was all rewritten to fulfill this vision. As the Versailles Treaty negated Germany developing or purchasing tanks of any kind, canvas covered vehicles were used in large-scale training exercises to validate the idea of mechanized warfare. One can only wonder at the bewilderment of there "tank" crews-in-training, driving automobiles while pretending them to be tanks. At the end of it all, it was agreed that the age of cavalry was over and the tank was the new king of the battlefield. Infantry still remained the heart and soul of any planned offensive, but the tank would become the spearhead of actions that could shatter enemy defenses through speed, force and firepower. Tactics involved the splitting up of enemy formations and counteractions involving pincer movements to surround and ultimately decimate the enemy in whole. With this kind of aggressive thinking, World War 2 had effectively arrived - the stage just needed its major players and a setting.

Much of Germany's military developments leading up to the official start of World War 2 was done in secrecy. In the early 1930's, the German Army called upon a few German firms to put together some funded prototype light and medium tanks. At this time, the Army did not have a formal plan of action in terms of what it realistically needed. Light tanks could be made available in large quantities for a relatively low price while medium tanks afforded firepower but came at a price. At any rate, the German industrial infrastructure - both the post-war limitations and the economical hit caused by the crash of 1929 - made the call easy for the Germany Army - the pursuit would be for the development of light tanks (at least for the moment).

An official requirement was put forth to secure a new light tank under a 5-ton weight limit that could serve as a competent crew trainer. Five German firms submitted prototype vehicles to which a design by Krupp was selected. Krupp looked for inspiration from the British Vickers "tankette" but fell behind in delivering anything of note by the summer of 1932. After some pressure by German Army officials, Krupp delivered - under the guise of a farm implement to the rest of the world - the La.S or "Landwirtschaftlicher" (roughly translating to "farm tractor", "industrial tractor" or "agricultural towing vehicle"). The Krupp tank had a Daimler-Benz superstructure and turret. Testing of the tank continued throughout 1934 by which time German Army assigned the designation of "Krupp-Tractor". This was more formally revised to the German Army designation of Pz.KpfW. I Ausf. A (Sd.Kfz. 101) in April of 1936.

In 1933, Adolf Hitler came to power and by 1934, he saw what he liked in the Panzer I. His vision of a new mighty German now entailed an army of fast-moving armored vehicles using tactics unlike the world had ever experienced. After witnessing the Panzer I first-hand, he ordered his subordinates to prepare for war within a short window of eight years. By 1935, Hitler announced that the Versailles Treaty was all but dead in Germany's eyes and they would no longer be bound to its limitations. The German Army came under the all-encompassing name of Wehrmacht and the nation forged ahead with its militaristic goals. The governments of the world, still weary from warfare just decades before and slowly trying to recover from the crash of 1929, did little in response.

Panzer I Ausf. A and the Rebuilding German Army

The Panzer I Ausf. A was the first German tank development in the post-war world. The diminutive system featured a crew of just two personnel -a driver and a commander, the latter doubling as the gunner. The driver sat in the forward hull of the tank (offset to left) while the commander occupied the turret (offset to right). The turret was rather simplistically-armed with 2 x 7.92mm machine guns (each firing at 650 rounds per minute, fired simultaneously or individually and afforded a total of 1,525 to 2,250 rounds of ammunition) and could only be traversed by the commander by hand. Entry and exit for the commander was through a turret roof-mounted semi-circle hatch while the driver could enter/exit by way of a hinged rectangular door alongside the left of the superstructure. Armor protection was minimal at best, made to withstand direct hits from small arms fire and little more. Armor thickness ran at just over half an inch at its peak depth. The Ausf. A featured five road wheels to a track side and each wheel was wrapped in rubber. Drive sprockets were located at the front of each track. Three rollers were fitted to the underside of the upper track rung. Operating weight was listed at 5.9 tons and power came from a single Krupp M 305 air-cooled, four-cylinder, gasoline engine delivering up to 60 horsepower. The Ausf. A could wield a top speed of 23 miles per hour with an operational range of 85 miles cross-country and 125 miles on road.

For a first attempt, Krupp produced a very solid design given the era and financial/industrial limitations. The turret gave the available firepower some flexibility to traverse while the overall layout was quite refined. The steel plate armor was angled at the hull, glacis plate, superstructure and the turret to help promote some level of crew survivability. Speed was impressive enough to make for a useful reconnaissance platform or troop support system and the relative small size meant that the little machine could make the system a tough target to zero in on while promoting ease-of-production values and making it affordable to the German Army in quantity. It should be noted, however, that not all German generals were sold on the Panzer I. Some thought it a rather limited affair with little to no real combat value for the modern military. In many ways, these individuals would be proven right.

With the design all set and approved, events were now pressed into motion to fulfill the light tank requirement in whole. Production was green-lighted and - to help maintain the production levels needed as required by the resurgent German Army - other German firms (including Henschel, MAN and Daimler-Benz) were brought into the fold to help support Krupp in its production efforts. Henschel received an initial batch order to produce 150 Panzer Is. 1935 also saw the first three Panzer divisions of the "new" German Army start to take shape.

Panzer I Ausf B: Bigger Engine and a Longer Hull

The Panzer I Ausf. B was introduced in August of 1935 with its liquid-cooled 100 horsepower engine. The original Ausf. A was fitted with a rather meager 60 horsepower air-cooled engine that made for less-than-stellar performance output. As such, the Ausf. B was revealed to help overcome the shortcomings of the initial production model. The Pz.KpfW. I Ausf. B featured a crew of 2 and a weight of 13,230lbs. The system was powered by a single Maybach NL 38 TR six-cylinder, liquid-cooled gasoline engine developing 100 horsepower. The engine was larger than the original 60hp offering and as such, the hull of the Ausf. A was lengthened to accommodate the new powerplant (the hull now measuring in at 14 feet, 6 inches). This also necessitated an additional road wheel per track side to compensate for the new length and weight. Performance figures included a top road speed of 25 miles per hour, a maximum road range of 87 miles, fording of up to 1 foot, 11 inches, gradient capability up to 60 percent, vertical obstacle capability of 1 foot, 2 inches and trench capability of up to 4 feet, 7 inches. Three hundred ninety-nine Ausf. B examples would be delivered by the end of 1937 to which production ceased in June of that year.

1936 showcased the Panzer I in large-scale maneuvers using both army infantry and Luftwaffe air elements. Also in 1936, Hitler committed "volunteer" German troops, aircraft and tanks to the Spanish Civil War (1936-1939) - a battleground that was effectively a "proving ground" for all things German. The Panzer I and her crews were one such implement sent to the region. Once there, the Panzer I did little to earn a positive legacy for itself. The tank proved inferior to the steel-armored Soviet T26 and B5 light tanks as these tanks were armed with a high-velocity gun that outmatched the twin 7.92mm machine gun offerings of the Panzer I. On many occasions, the German tanks were destroyed well before they ever reached within range of their own useless machine guns. While adaptation of a 20mm cannon was noted on some of these Panzer Is, the system was still of little combat value on the modern battlefield. In essence, the coming out party was a complete failure though the tank's value as a reconnaissance platform, infantry support system and crew trainer were still of some note. More importantly, the basis of the "Blitzkrieg" was being refined right under the nose of the world. A full six Panzer divisions were made available by September of 1939 to which - by this time - at least Poland would take note.

On September 1st, 1939, elements of the German Wehrmacht - including Panzer Is - poured across the Polish border. The Germans held some 1,400 of Panzer Is at the ready during the invasion. Defenses were soon overwhelmed by the combined land and air power being unleashed by the Germans. In the campaign, the Panzer I proved to be adequate despite its less-than-stellar outing in the Spanish Civil War. It was by no means a front line vehicle but its uses were still apparent. There were also no Soviet tanks to encounter along the Polish frontier. Interesting to note later in the war - some 500 Panzer Is were used during the invasion of the French countryside though many more were available throughout Germany and Poland. Perhaps a testament to the changing requirements of the modern battlefield or lack of trust in the Panzer I system to spearhead the more-prepared defenses of France.

Panzer I Ausf. C: Bigger Gun, Bigger Engine and More Armor But Somewhat Limited

By 1941, the Panzer I Ausf. A models had all but met their usefulness on the ever-changing battlefield. Their weak machine gun armament coupled with their weak armor allocation relegated them to become either conversion models or semi-capable kleiner Panzerbefehlwagen I (Sd.Kfz 265) command-and-control vehicles. To address the armor weakness of the Ausf.A and Ausf. B, Krauss-Maffai developed the Panzer Ausf. C to include 1.2-inches of frontal armor. The armament was further addressed to include a 20mm autocannon in place of one of the two original machine guns (the second machine gun was wisely retained as an anti-infantry weapon). As can be expected, the addition of both the cannon and armor drove up the weight of the Ausf. C. to the point that a more powerful Maybach liquid-cooled gasoline engine of 150 horsepower was introduced. A torsion bar suspension system was also implemented as were large overlapping road wheels, netting the vehicle a top speed of 49 miles per hour. Despite the benefits in the revised design, it was still wholly outclassed by the new Allied tanks coming online and therefore only 40 Ausf. C models were ever produced.

Panzer Ausf. F: Like the C, Only Better-Armored But Heavier and Equally Limited

The Panzer Ausf. F followed along the same lines as the improved Ausf. C models but these were developed with the distinct role of infantry support in mind. The Panzer I was never a tank system that was going to go head-to-head with anyone - the Spanish Civil War proved just that, as did the invasion of Poland and France - but the system still retained some inherent usefulness in the eyes of some. With improved armor protection, it was seen that the "little system that could" still had some life in her yet. The Ausf. F improved frontal armor protection to a full 3.2-inches while side armor was increased to 2-inches. Interestingly, the new variant retained the Panzer I original armament of 2 x 7.92mm machine guns (aimed via a 2.5-power optical telescope). The tank treads were noticeably wider and the road wheels were overlapped on either side. The hull was taller and sported a stout look from any profile while the turret was centered on the superstructure and set closer to the center of the design. By now, the original 6-ton Panzer I had ballooned to nearly 20 tons (approximately 22,046lbs) naturally suffering a performance hit to its maximum road speed. However, like the Ausf. C before it, the Ausf. F was viewed as having limited uses on this new battlefield so a limited production run was ordered totaling just 40 vehicles. At least eight Ausf. Fs were fielded along the East Front while others made it to actions across Yugoslavia and Greece. Production was handled by Krauss-Maffei from the middle of 1940 to the latter part of 1942 to which some 30 examples were produced.

Panzer I Conversions

Despite the limited value of the Panzer I's original armament, the chassis proved another story. Beyond the aforementioned kleiner Panzerbefehlwagen I (Sd.Kfz 265) command-and-control vehicles (one of the earliest battlefield uses of such a system), the Panzer I chassis made up other perhaps lesser-known developments. One of the earliest hull conversions became the Munitions-Schlepper charged with carrying ammunition or supplies as required. Some former Panzer Is were unveiled in the North Africa campaign as flamethrower tanks in the "Flammenwerfer auf Panzerkampfwagen Ausf A" models, taking part in the Battle of Tobruk of 1942. Still other Panzer Is were stripped of their turret tops and fitted with captured Czechoslovakian 47mm cannons for use on the West Front, in North Africa and in the invasion of the Soviet Union beginning 1941 as mobile anti-tank systems. This became one of the earlier anti-tank chassis conversions utilized by the German Army. Any student of the war will note that the German Army became experts in such conversions as the war progressed. The 47mm-armed Panzer Is were quickly outmoded as Allied armor continued to improve with time and battlefield experience.

At least 100 original Panzer Is were used to build the Ladungsleger auf Panzerkampfwagen I Ausf A / B, engineering vehicles used in laying down explosive charges. Further modified Panzer I chassis became the Flakpanzer anti-aircraft defense systems that operated up until about January 1943. The Sturmpanzer "Bison" (sIG-33) was a rather simple heavy mortar carrier conversion that mounted a 15-cm main gun in an open-topped armored superstructure. The system was limited in carrying only three 15-cm shells and such limitations led to only 40 conversions. Perhaps one of the more interesting uses of the Panzer I was in the implementation of their turrets to serve as fixed defensive emplacements along the Atlantic Wall and throughout the German Eastern defenses.

End of the Road

While the Panzer I saw notable action in the early part of the war, nearly all were lost in combat by 1944. The changing requirements of the German Wehrmacht ultimately left little room for "light" tanks anyhow and the army became more persistent in devising capable tank-killers at the expense of speed, production simplicity and engine reliability. The Panzer I was inevitably superseded by the improved Panzer II which was already in development as early as 1936. Production of the Panzer II would begin in 1937. If the Panzer I proved anything it was that the old way of doing business on the battlefield had changed. Its inception also came about at that "perfect" time in history, a time when German doctrine necessitated the need for such a weapon. It proved the original German army vision of high mobility with coordinated attacks was the key to dismantling pockets of concentrated enemies. No doubt the way of the Blitzkrieg opened up a new era of mechanized warfare, one that has since been copied time and time again.

Perhaps most recently, the United States invasion of Iraq in 2003 - where coordinated attacks by land, sea and air yielded equally effective and (devastating) results on the Iraqi Army through the use of "Lightning War" - though this time it came under the guise of "Shock and Awe".
SdKfz 101 Panzerkampfwagen I (PzKpfW I) / Panzer 1 Specifications
National Flag Graphic
Nazi Germany
Year: 1935
Type: Light Tank
Manufacturer(s): Krupp / Daimler-Benz / Wegmann / Henschel - Germany
Production: 2,800
Supported Mission Types
Troop Transport
Infantry Support
High Mobility
Tank Destroyer
Special Forces
Towed Artillery
Self-Propelled Artillery
Rocket Artillery
Airspace Denial
Special Purpose
Crew, Dimensions and Operating Weight
Operating Crew: 2
Length: 14.50 ft (4.42 m)
Width: 6.76 ft (2.06 m)
Height: 5.64 ft (1.72 m)
Operating Weight: 7 ft (6,000 kg; 13,228 lb)

Installed Power
1 x Maybach NL 38 TR 6-cylinder engine developing 100 horsepower.

Base Performance
Maximum Road Speed: 25 mph (40 km/h)
Maximum Road Range: 87 mi (140 km)

Armament and Ammunition
2 x 7.92mm machine guns in turret

1,525 to 2,250 x 7.92mm ammunition

Optional Systems
Nuclear-Biological-Chemical (NBC) Protection: None
Nightvision (NV) Equipment: None

Operators List
Nazi Germany

Model Variants
• Landwirtschaftlicher Schlepper - "Industrial Tractor" Vehicle Cover Name.
• Pz.Kpfw I (Sd.Kfz 101) Ausf. A - Initial Production Model Series Designation; fitted with Krupp M 305 57hp air-cooled four-cylinder engine; 6-ton weight.
• Pz.Kpfw I Ausf. B - Second Production Model Designation; fitted with Maybach NL 38 TR 6-cylinder liquid-cooled engine of 100hp; longer hull; extra pair of road wheels; produced by Henschel and (later) Wegmann.
• Pz.Kpfw I Ausf. C - Improvement of 1.2 inch frontal armor protection; 1 x 20mm autocannon in turret retaining 1 x 7.92mm machine gun; Maybach liquid-cooled gasoline engine of 150 horsepower; torsion suspension bar; large overlapping road wheels; 40 examples produced.
• Pz.Kpfw I Ausf. F - Improvement of 3.2 inch frontal and 2 inch side armor protection; 2 x 7.92mm machine guns in turret; 20-ton weight; redesigned hull; centered turret; wider tracks; overlapping road wheels; 30 examples produced.
• kleiner Panzerbefehlwagen I (SdKfz 265) - Command-and-Control Vehicle utilizing Panzer I chassis.
• Munitions-Schlepper - Ammunition/Supply Cargo Carrier Conversion Model
• Flammenwerfer - Flamethrower Tank Conversion Model.
• Panzerjager I, 4.7-xm PAK(T) - Fitting Czech 47mm gun in open-topped turret; anti-tank conversion model.
• Ladungsleger auf Panzerkampfwagen I Ausf A/B - Engineer Vehicles
• Flakpanzer - Anti-Aircraft Defense Artillery Conversion Model
• Sturmpanzer Bison (sIG-33) - 15-cm (150mm) Mortar Gun Carrier; 3 x mortar shells; 40 examples produced/converted; Maybach NL 38 TR engines of 100 horsepower; 13mm armor protection; crew of four; 8.5-ton weight.

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